1. Field of the Invention
The present invention is concerned with sliding windows intended to serve as automobile windows and in particular with a window, in the shape of a sector, which pivots about an axis.
2. Description of the Prior Art
Traditionally, flat windows slide in their plane, following a straight path, either vertical or horizontal. Generally, the window has a simple geometric shape, in which two opposite parallel sides are guided in grooves forming the frame of the window. In the case of windows sliding horizontally, the window may be divided into two glass sections of approximately the same size and the sections slide on their respective guide rails with relation to one another. It has been common practice to put the section of the window which is outermost with respect to the plane of the car door towards the front of the vehicle so that its overlap with the so-called interior section of the window will impede the undesirable entry of air due to the speed of the vehicle when the two windows are in the closed position. It is known, as well, for the overlap of the windows, that a small inclination with respect to the vertical may serve to impede the entry of rain.
All these methods have their advantages, but they also have several deficiencies where comfort is concerned. For example, the area exposed by the complete opening of one of the windows remains rather small and makes difficult, if not impossible, any operation by the driver requiring access to the immediate exterior vicinity of the window. These exterior operations are rather frequent, whether for easy access to the exterior rear view mirror, to permit its adjustment, or for any other action not requiring exit from the vehicle, such as is the case for payment of tolls at a manual or automatic toll booth or in a parking lot, for example. It is also the case when the driver finds it necessary to lean his head outside the window in order to back up with better visibility.
Furthermore, the weight of the window is supported by the lower edge in sliding contact with the straight guide rail. The coefficient of friction is thus significant and frequent use of the window eventually leads to premature wear of the track and to more and more difficulty in sliding the window. Increased play between the window and the guide rail may also make the window twist slightly in the plane with respect to its direction of movement, while being operated, and the slight blockage which results thus interferes with the proper functioning of the window, which then slides jerkily and thus lacks smoothness.
A window treatment is already known in the shape of a sector, mounted on the rear lateral wall of a vehicle, and whose single window, having the same shape, pivots about an inferior axis by means of an articulated system housed in the interior of the body.
This configuration is not conveniently applicable to a forward window treatment since the glass sector is a quarter of a circle, and consequently the field of visibility and accessibility to the exterior would be even more limited than for a rectilinear sliding window with parallel sides. Moreover, the axis of rotation, located at the lower part of the window, puts it in an unstable equilibrium. Thus one is obliged to envision a retaining system such as the aforementioned articulated system.